1. Field of the Invention
The present invention relates to the use of a heatable and flexible mat in the manufacture of an orthosis.
2. Description of the Related Art
It is well known to manufacture an orthosis, by heating a sheet of thermoplastic material to a temperature at which the sheet softens to a state in which it can be readily shaped, wherewith the warm and softened sheet can be applied to a relevant part of a patient's body and shaped to provide the support intended, whereafter the orthosis is allowed to cool and solidify to provide the intended support. The sheet of material may, of course, be cut to provide an orthosis of appropriate size, either before or after shaping the sheet.
An orthosis technician will often visit a patient, for example a hospital visit, with the intention of manufacturing an orthosis for the patient concerned. For instance, a patient may have a broken leg and the entire leg may be encased in plaster, whereafter having first established that the healing process has proceeded as desired, the doctor concerned will prescribe removal of the plaster and its replacement with an orthosis placed over the fracture region, so as to enable the patient to walk or move with mobility in his/her knee joint.
The orthosis technician will normally bring with him one or more sheets of varying sizes and shapes, and also of different thicknesses. The technician may also bring with him an industrial hot-air gun with which to soften the sheet, by blowing a stream of hot air thereon. This procedure is afflicted with several problems. One problem is that the power consumed by the electrically operated hot-air device in softening the sheet over the whole of its area is relatively high, in the order of 3,000 watts, which often results in a blown fuse, with well known drawbacks as a result. Furthermore, a hot-air gun is very noisy in operation. U.S. Pat. No. 3,906,943 describes softening of the orthosis sheet with a hot-air gun or a heating plate.
One problem with this solution is that the technician is not certain of how uniformly the sheet of material has been heated, meaning in practice that the sheet may have sub-areas which have not been softened to an extent that will enable the sheet to be shaped comfortably and correctly on the patient.